Feed pawls for loom batteries



May 10, 1960 L. G. URQUHART FEED PAWLS FOR LOOM BATTERIES 2 Sheets-Sheet 1 Filed Sept. 14, 1956 w 1y WK.

May 10, 1960 L. e. 'URQUHART FEED PAWLS FOR LOOM BATTERIES Filed Sept. 14, 1956 2 Sheets-Sheet 2 nited States Lloyd G. Urquhart, Westboro, Mass, assignor to H. F. Liverrnore Corporation, Allston, Mass., a corporation of Delaware Application September 14, 1956, Serial No. 609,928

Claims. (Cl. 139-250) This invention relates to looms, and in particular to the parts of the rotary magazine'or battery used in automatic looms of the Draper type to present new bobbins in position for transfer to the shuttle when weft replenishment is called for. Rotation and positioning of the revolving disk which feeds and holds the bobbins in transfer position is effected by a feed pawl pivotally mounted on the transferrer and engaging a ratchet formed integrally on the bobbin disk. The feed pawl works in conjunction with a holding pawl which locks the bobbin disk in position, all as well known.

The feed pawl in these looms as built is formed with a stud extending laterally, driven into and permanently fixed therein, which is received in a hub formed on the top of the transferrer and thus serves as the pivot for the feed pawl. The spring needed to hold the feed pawl against the ratchet is coiled aboutthe hub on the transferrer with its ends hooked around the transferrer and feed pawl respectively, or else wrapped around the protruding end of the stud with one end through a hole therein, the other end being hooked around the feed pawl. Thus the spring both retains the feed pawl on the transferrer and exerts torque on the stud to hold the feed pawl against the ratchet.

As a result of loom vibration and the recurring violent action of the transferrer, rapid wear develops between this stud and its bearing surfaces inside the hub of the transferrer. Thus replacement of thefeed pawl is a recurring item of repair and upkeep on battery looms because =of wear resulting in improper bobbin positioning, as well as through breakage.

Such replacement involves the cost of new parts,; including the transferrer when the transferrer hub holding the pivot of the feed pawl wears too large or out of round; such transferrers are normally thrown away. But, what is worse, it is a time wasting job, requiring minutes or more of shut-down time of the loom. The transferrer must be loosened and shifted along its stud and away from the bobbin disk in order to make room enough to get the feed pawls pivot stud out of the hub in the transferrer and extricate the feed pawl from between these two parts. Moving the transferrer involves releasing and later retensioning its powerful spring, coiled around its hub with one end threaded through a hole in the stud or seated in a hole on a bushing pinned to the stud. It further compels shifting of the weft parter mounted on this stud and loss of its critical adjustment,

which must be painstakingly reestablished before the loo can go back to work.

The main object of the present invention is to simplify the job of replacing damaged feed pawls, and thus to shorten greatly the time required for the replacement. An additional object is to prevent wear of the transferrer by the feed pawl, and thus to eliminate the practice hitherto compelled thereby of discarding and replacing the transferrer also. A further important object is to cut down the wear and wabble of the feed pawl, making it last longer and avoid destructive malfunctioning.

Other objects of the invention are as will be made plain hereinafter.

To these ends, in accordance with the invention, the

feed pawl is pivotally mounted on a pivot which is mounted on the transferrer in quickly-detachable relation thereto and made of such shape and proportion as to be easily inserted into the existing hub on the transferrer after the feed pawl has been put in place on such pivot, and equally easily removed from the transferrer hub, in both cases without disturbing the working relation of any other parts of the loom structure. That is, the feed pawl with its pivot are adapted to be inserted into the transferrer, and to be removed therefrom, via the normal scant existing space between the transferrer and'the bobbin disk. Sincefthe new pivot is operatively fixed in the transferrer hub, no wear of the transferrer occurs at this point. Other features of improvement and advan-g tages are as indicated hereinafter.

An illustrative embodiment of the invention is shown in the accompanying drawings, in which Fig. 1 is a side elevation of a portion of the battery with full bobbins therein and other parts of the weft replenishing mechanism at the battery end of the loom, showing the feed pawl in place.

Fig. 2 is an exploded perspective view of the novel feed pawl and its mounting, shown in connection with the standard Draper type transferrer.

Fig. 3 is a side elevation, and Fig. 4 a front view of the novel feed pawl.

Fig. 5 is an alternative form of pivot for the feed pawl.

Fig. 1 shows the main parts at the weft-replenishing end of a typical Draper battery loom, in which 1 is the bobbin disk with its integral ratchet 3 and notches 5 receiving the butts of the full bobbins 7. The transferrer 9 is pivoted upon stud 11 fixed on bracket 13 on the breast beam 15. The parts are shown in their relation at the completion of the transferrers downward stroke, after it has driven a fresh bobbin 17 into the shuttle 19 occupying the shuttle-box at the replenishing end of the lay 21.

The novel feed pawl 23 is in most respects of conventional design and function, having the usual dog 25 for engagement with the teeth of ratchet 3 and the cam 27 to engage the projection 30 on the holding-pawl 32 on the down-stroke of the transferrer 9 to keep the hold ing pawl in the ratchet and on the up-stroke to free the holding pawl as the dog 25 on the feed pawl engages the ratchet to bias and eventually feed thebobbin disk around one step so as to bring the next bobbin 7 into waiting position beneath the transferrer after the latter has recoiled, It also has the usual finger-piece 29 for manual operation.

However, unlike its predecessors, there is no stud or pivot fixed in the feed pawl. Instead, it has a hub 31 of generous diameter, within which is slidably fitted a pivot 33 having a shank of two different diameters, a threaded bore, and a hexagonal head. The shank portion 35 of smaller diameter is immediately adjacent'the portion 41 of larger diameter, with no intervening enlargement, and is made to fit easily within the bore of hub 37 provided on the top edge of. the standard Draper transferrer 9 for the reception of the stud of the prior type feed pawl. Thus this portion 35 has substantially the diameter of the older stud which formed a permanent part of such prior feed pawls. The portion 41 of pivot 33 of larger diameter fits the bore of hub 31 on feed pawl 23, and forms the mounting and supporting surface of liberal dimensions on which'the feed pawl pivots. Hexagonal head or flange 43 retains the feed pawl on the pivot 33 by engagement with the side of hub 31, and aids in holding the feed pawl accurately in its intended vertical plane.

The pivot 33 is mounted in fixed relation within trans ferrer hub 37 by means of a cap screw 45 threaded into the screw-threaded bore 47 ofpivot 33, a lock washer 49 and flat steel washer 51 being interposed between the head of the screw and the proximate end of hub 37. Shank portion 35 is slightly less in length than hub 37, so that when screw 45 is tightened the pivot 33 is held in fixed and non-rotating working relation within the passage of hub 37. In actual practice, the passage 47 is extended all the way through the pivot 33, for economy and convenience in manufacture, so that this pivot in effect is a form of bushing.

The shape and proportion of the relative parts of pivot 33 permit the novel feed pawl and its pivot to be inserted together into place on the transferrer without moving the latter out of its working position. The existing clearance between the transferrer and the bobbin disk is sufiicient to admit the hub 31 of the pawl 23 with the pivot in place in the hub 31 of the pawl while the latter is tilted over the transferrer. All parts of the length of the pivot except flange 43 being less in diameter than that of the passage through hub 31, the difference in the diameters of the two portions 35 and 41 permits the pivot 33 to be brought into axial alignment with the bore of transferrer hub 37 so as to enter such bore while the pawl is still tilted and its hub 31 is on the reduced portion 35. Then the pawl is erected into parallel with the bobbin disk and transferrer, the larger hub 41 of the pivot enters the hub 31 of the feed pawl, and the reduced portion 35 slides home into the transferrer hub 37 until the shoulder 53 brings up against the end of transferrer hub 37. Screw 45 is then entered into passage 47 and tightened, thus completing the installation of the feed pawl.

The thin head 43 of the pivot leaves just enough space I between the bobbin disk and itself to enable one finger of the fixers hand to guide the pivot into place and hold it securely during the operation, the head of course being held with a wrench while screw 45 is finally tightened. Removal of the pawl and its pivot is efiected by a reversal of this process, as will be clearly understood.

This construction affords an easy means for accurately adjusting the length of the working stroke and maintaining the proper working relation between the feed pawl and the ratchet as well as between the feed pawl and holding pawl. This is simply effected as shown in Fig. 5, by making the pivots shank portion 61 eccentric with respect to the axis of the reduced portion 63. By turning the pivot about its axis, with clamping screw 45'momentarily loosened, of course, the range of movement of the dog 25 while in contact with the ratchet 3 admits of being varied within the limits of eccentricity of portion 41 with respect to the axis of the pivot. In the present device, the usual spring 55 is provided to make the feed pawl advance the bobbin disk the rest of its intended travel as soon as the head of the transferrer rises above and out of contact with the next bobbin to be transferred. This spring is coiledaround the hub 31 of the transferrer, instead of being wrapped around the stud fixed in the prior type of feed pawl with its end put through a hole therein. One end of the spring 55 is hooked around the lug 57 on the transferrer just forward of its hub 31, while the other end is bent in zigzag form with its extremity hooked under the forward end of the feed pawl and with a bend pressed against the front of finger lever 29 on the feed pawl.

As already indicated, this new construction makes it a matter of utmost simplicity to remove and replace a damaged or worn feed pawl. Since no disturbance of the working relation of any of the parts of the weft replenishing mechanism, including the weft parter is needed, the job is effected quickly and easily with a minimum loss of machine time. The novel structure prevents any wear of the bore of transferrer hub 31 since there is no relative motion of the parts therein. In addition to thus eliminating the scrapping of transferrers from this cause, it makes it easily possible to ream out the hubs of worn transferrers and apply the device of the invention thereto to 4 restore their usefulness, merely by increasing the diameter of the reduced portion 35 of a pivot 33 to match the diameter of the transferrer hub thus rebored.

While I have illustrated and described a certain form in which the invention may be embodied, I am aware that many modifications may be made therein by any person skilled in the art, without departing from the scope of the invention as expressed in the claims. Therefore, I do not wish to be limited to the particular form shown, or to the details of construction thereof, but

I claim:

1. In a rotary bobbin magazine for automatic looms, in combination, a rotary disk engaging the bobbin butts, a ratchet adapted to rotate the disk, a transferrer having a hub, a feed pawl having a hub, and pivot means extending through both hubs forming the pivot for the feed pawl having a pawl-retaining flange on its end nearer the disk and a shoulder adapted to pass through the feed pawl hub and then engage the transferrer and also having an internally threaded bore, and screw means engaging with such bore and bearing against the transferrer retaining the pivot means in the transferrer.

2. In a rotary bobbin magazine for automatic looms, in combination, a rotary disc engaging the bobbin butts, a ratchet adapted to rotate the disc, a transferrer having a hub with a passage therethrough, a feed pawl having a hub with a passage therethrough, and means extending through both hubs forming the pivot for the feed pawl and having a pawl-retaining flange on its end nearer the disc, the remainder of its length being at all points less in diameter than that of the passage through the hub of the feed pawl, a portion of such length supporting the feed pawl and another portion of reduced diameter being fixed in the transferrer.

3. In a rotary bobbin magazine for automatic looms, in combination, a rotary disk engaging the bobbin butts, a. ratchet adapted to rotate the disk, a transferrer having a hub, a feed pawl having a hub, and pivot means extending through both hubs forming the pivot for the feed pawl having a pawl-retaining flange on its end nearer the disk and the remainder of its length less in diameter than the passage through the feed pawls hub and having a shoulder engaging the transferrer hub and a portion fixed in the transferrer hub.

4. In a rotary bobbin magazine for automatic looms, I

in combination, a rotary disk engaging the bobbin butts, a ratchet adapted to rotate the disk, a transferrer having a hub, a feed pawl having a hub, and pivot means extending through both hubs forming the pivot for the feed pawl having a pawl-retaining flange on its end nearer the disk and the remainder of its length less in diameter than the passage through the feed pawls hub and having a shoulder engaging the transferrer hub and a portion fixed in the transferrer hub and less than the thickness of the transferrer hub.

5. In a rotary bobbin magazine for automatic looms, in combination, a rotary disk engaging the bobbin butts, a ratchet adapted to rotate the disk, a transferrer having a hub, a feed pawl having a hub, and pivot means extending through both hubs forming the pivot for the feed pawl having a pawl-retaining flange on its end nearer the disk, a portion of circular section fitting within the feed pawls hub, and an adjacent portion of circular section and reduced diameter fitting within the transferrer hub and passable through the feed pawls hub with its axis oblique to the hub in order to enter the transferrer hub, and means fixing this portion in the transferrer hub.

References Cited in the file of this patent UNITED STATES PATENTS 1,019,855 Stirnpson Mar. 12, 1912 1,269,975 Stimpson June 18, 1918 1,581,597 Poirrier Apr. 20, 1926 2,033,971 Bahan Mar. 17, 1936 2,074,910 Hilton Mar. 23, 1937 

